How do you grapple with being grateful but wanting more?

I have started to express gratitude in my life more than ever, and I have noticed considerable positive changes in my level of happiness and contentment. I even go as far as to write down 5 things in my day that I am grateful for before going to bed. With that said, what are some strategies for balancing gratitude with moving forward, with realizes goals, dreams and aspirations? For example, say a single mother is able to just barely put food on the table for her children one night...Wonderful! To express gratitude in that moment is health-producing and powerful. However...what if she wants more than just barely making ends meet? How does one negotiate feelings of gratitude with striving do do better, be better, have better? Any thoughts on this would be great, thank you!